Phylogeny and Diversification in Mollusc
The first molluscs probably arose during Precambrian times because fossils attributed to Mollusca have been found in geological strata as […]
Phylogeny and Diversification in Mollusc Read More »
Lead
An Introduction to Class Oligochaeta
Class Oligochaeta More than 3000 species of oligochaetes are found in a great variety of sizes and habitats. They include
An Introduction to Class Oligochaeta Read More »
Class Bivalvia
Bivalvia are also known as Pelecypoda (pel-e-sip o-da), or “hatchet-footed” animals, as their name implies (Gr. pelekys, hatchet, pous, podos,
Class Cephalopods
Cephalopoda (Gr. kephal¯e, head, + pous, podos, foot) include squids, octopuses, nautiluses, devilfish, and cuttlefish. All are marine, and all
Representative Polychaetes: Common Worms
Clam Worms: Nereis Clam worms, or sand worms as they are sometimes called, are errant polychaetes that live in mucous-lined
Representative Polychaetes: Common Worms Read More »
Gastropoda: Internal Form and Functions
Respiration in most gastropods is performed by a ctenidium (two ctenidia is the primitive condition, found in some prosobranchs) located
Gastropoda: Internal Form and Functions Read More »
Major Groups of Gastropods
Traditional classification of class Gastropoda recognizes three sub classes: Prosobranchia, the largest subclass, almost all of which are marine; Opisthobranchia,
Major Groups of Gastropods Read More »
Dividing the Body among Animals
Although a fluid-filled coelom provided an efficient hydrostatic skeleton for burrowing, precise control of body movements was probably difficult for
Dividing the Body among Animals Read More »
Temperature Structure of the Atmosphere
In general, the air is cooler at higher altitudes. Most incoming solar radiation passes through the atmosphere and is absorbed
Temperature Structure of the Atmosphere Read More »
Temperature Contrasts: Urban and Rural
On a hot day, rural environments will feel cooler than urban environments. In rural areas, water is taken up by
Temperature Contrasts: Urban and Rural Read More »
